Decollete

a.	1.	Leaving the neck and shoulders uncovered; cut low in the neck, or low-necked, as a dress.
	2.	Wearing a décolleté gown.

Adj.

1.

decollete - (of a garment) having a low-cut neckline; "a low neckline" Synonyms: low-cut, low-necked

low-cut, low-necked, necked